Stuart McCall took full responsibility for a “hugely disappointing” defeat, after the Bantams fell 3-0 at home to Newport County.
City were comprehensively beaten by the table-topping Exiles at the Utilita Energy Stadium, after first conceding just 45 seconds in.
McCall blamed the change in tactics he implemented for the defeat, and took the blame.
He said: “Disappointed does not even sum it up, to be honest.
"We were playing against a very good side, who are top of the league, and went a goal down after 45 seconds.
“Having said that, I take full responsibility. I tried to play a system which put three of our players against their back three.
“They have had two clean sheets in their past couple of games and look comfortable. They are in a routine of playing, and I just wanted to see if we could dismantle that, by getting at them.
“That clearly did not work and we changed it at half-time. We started the second half better but had a little period where we were giving the ball away, and never really laid a glove on them.
“It is hugely disappointing, naturally, and is still raw to speak about, but we did not get off to a good start and never really recovered.
“We begun poorly and allowed a good team to sit tight and defend and break well. We were beaten by the far better side.
“We needed to get a goal back and did not get one - and we never really looked like getting one, to be honest.
“We had to be at our best today and were certainly not. There are no excuses to be made.”
After his side’s heaviest league defeat of the season, the Bantams boss has now turned his attention to a reaction in City’s next outing.
McCall’s men travel to Bolton Wanderers on Tuesday evening and the former Scotland international has stressed the importance of a response.
The City chief added: “The reaction on Tuesday is important. We are early on in the season and this was not a result we wanted.
“The past few home games have been nowhere near good enough, but it is to us to make that better.
“We need to be able to get an early goal, which we did at Mansfield.”
“You saw there how much of a positive impact it can have on the game, and how much confidence we can build from it.
“It is now about how much we want to go to Bolton on Tuesday and put in a performance and get a result like we did earlier on in the season.”
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